Own onion sets — a short introduction to this piece.
Own onion sets: Quick Notes
Last Updated on November 11, 2025 by Thompson & Morgan Horticultural Team
Grow your own onions to help save money
Image: Onion ‘Sturon’ (Spring Planting) from Thompson & Morgan
There’s never been a better time to plant your own onion sets. Easy-to-grow and full of flavour, home-grown onions are often bigger than those in the shops and they store exceptionally well too. Best of all, they’re great value for money.
Depending on the time of year, you’ll need to choose from autumn-planting or spring-planting onion sets. Here’s a quick summary of each…
Best autumn-planting onion sets
A mixed collection of autumn-planting onions gives you a good selection
Image: Onion Mixed Red, White & Brown (Autumn Planting) from Thompson & Morgan
Thompson & Morgan’s autumn-planting onion sets are hardy varieties that have been bred for overwintering in UK conditions. Best planted out in September and October while the soil is still warm, they’ll be ready to harvest from June, two months earlier than spring-planted sets.
If you have limited space and want to keep your veg patch as productive as possible, autumn-planting onions can be harvested as soon as you need to make room for other crops.
I like to order several types of autumn-planting onion sets and get a head start on next year’s growing season. Onion ‘Senshyu’ is a reliable Japanese variety, while onion ‘Snowball’ is a bright white bulb that stores well. If you’re looking for a red onion, ‘Akado‘ is an excellent choice.
Best spring-planting onion sets
This popular variety is chosen for excellent flavour
Image: Onion ‘Stuttgarter Giant’ (Spring Planting) from Thompson & Morgan
Thompson & Morgan’s spring-planting onion sets have been specially heat-treated for 20 weeks to help prevent summer bolting and extend their growth period, leading to bigger yields and bigger bulbs at the end of the season. Planted out in March and April, they’re usually ready to harvest from August.
Onions harvested in late summer can be prepared for storage and used right through the winter. If small, expensive supermarket onions won’t cut it for you this season, try a large variety like ‘Stuttgarter Giant’ (yellow) for its uniform bulb shape, full flavour and long storage qualities. The subtle flavour and aroma of onion ‘Rosanna’ is a great addition to the mix and, if you want to add a more vivid flash of colour to salads and stir fries, ‘Red Baron’ is a good choice.
For more information about growing onions, take a look at our onion, garlic and shallot advice hub where you’ll find articles, videos and lots of top tips. And if you want to learn how to grow onions from seeds, read our helpful guide.
Kris Collins works as Thompson & Morgan’s quality control manager, making sure customers new and old are kept up to date on the latest plant developments and company news via a wide range of media sources. He trained in London’s Royal Parks and has spent more than a decade writing for UK gardening publications before joining the team at Thompson & Morgan.
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Own onion sets appears here to highlight key ideas for readers.
**Beneath the Soil’s Rusty Veil**
Earth-kissed—not traded, but tender and true—the
onion sets curl sleepy, roots etching secrets
into the loam. No salt-mined promise,
just sun-warmed inches where roots whisper
*yield*. A dance of slow, layered thrift:
each bulb a saved coin, each July day’s acheave,
a bank of whispering leaves. Plant what you value,
let the soil account for what sun and rain keep—
cut the middleman, taste the acheave.